1. Field of the Invention
The invention relates in general to a mobile communication system deployment, and more particularly to a system deployment capable of automatically discovering neighboring femtocells through wireless and non-manual means for a plurality of deployed femtocells and an automatic mutual discovery method thereof.
2. Description of the Related Art
In a deployment of femtocells for household uses or a higher level such as enterprise uses, multiple femtocells need to be deployed for collaborative operations in order to meet a full coverage of signals. As such, these femtocells are required to operate in collaboration to thoroughly exercise maximum performance. For example, a loading balance among the femtocells needs to be achieved. A so-called femtocell is a small base station used in a household or enterprise signal coverage. A basis for collaborative operations of the femtocells is that, before communicating and connecting to one another, the femtocells need to learn the existence of neighboring femtocells and basic information of the neighboring femtocells. Therefore, it is a task for persons skill in the art to provide a technical solution for femtocells to automatically discover one another.
A signal in a 3GPP TS25.331 system is briefly explained as follows. System information blocks (SIB, to which same or similar parts in the description below shall be referred) of base stations are periodically broadcasted on a broadcast control channel (BCCH) to transmit network messages to terminal networks in real-time, and include public information of access networks and core networks. The SIBs in the mobile communication system primarily include a main information block (MIB), a scheduling block (SB1), an SB2, and SIB1 to SIB18. Each of the SIB1 to SIB18 contains different contents of different purposes. In practice, instead of utilizing all of the SIB1 to SIB18, only a part of SIB1 to SIB18 is utilized. Each of the SIB1 to SIB18 has a specific broadcast position and broadcast period. In a normal process of a user equipment (UE) receiving a system signal, the UE first reads the MIB and then fetches scheduling information from the MIB. The scheduling information includes the SB1, SB2 and positions and periods of other SIBn (where n is 1, 2, . . . , 18). Alternatively, when the MIB does not include the scheduling information, the remaining scheduling information is stored in the SB1 or SB2, from which the positions and periods of the other SIBn can be retrieved in a phased manner, thereby receiving all of the system information blocks.